Avast is continually scanning my image files - why?

[Qhubarb]

I'm using Avast 4.7 on windows Vista and have noticed that it seems to be continually scanning. (the little icon was spinning around).  On closer inspection the "Standard Shield" program shows that it is scanning through my photos in the pictures folder.
Does anyone know what would be causing these files to be opened and hence scanned?
Thanks!

[Lisandro]

Maybe the Windows indexing service running in background...
Maybe any picture management tool (like Picassa) is scanning your drive for pictures...
Is your sensitivity level High or Normal (Standard Shield)?

[Qhubarb]

Thanks for your help, I did some further research and I managed to discover that it was the process "searchprotocolhost" which was opening the image files. Aparently this is the Windows indexer, it did eventually stop scanning I guess once it had got through all the files.

[Lisandro]

Thanks for posting...
You can (not should) exclude files from scanning.
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